1. Field of the Invention
This invention relates to a recording/reproducing apparatus and a recording/reproducing system for recording/reproducing information signals for a recording medium.
2. Description of the Related Art
Up to now, recording/reproduction of information signals for a flexible disc is executed bu a recording/reproducing apparatus having a magnetic head. In recording/reproducing information signals, the magnetic head is moved to a desired data track.
Specifically, there are formed plural data tracks on the recording medium. For this recording medium, the recording/reproducing apparatus moves the magnetic head to a desired data track to record/reproduce information signals. In certain types of the recording medium, the position information of each data track is stored. In such recording medium, the recording/reproducing apparatus shifts the magnetic head to the desired data track based on the position information.
Up to how, it is known to use a stepping motor as driving means for a magnetic head. In a majority of cases, the recording/reproducing apparatus is controlled by an external computer. In this type of the recording/reproducing apparatus, the magnetic head is moved by the stepping motor, responsive to a track feed request pulse supplied from the external computer, in an amount corresponding to the specified number of pulses.
Meanwhile, in a recording/reproducing apparatus, the magnetic head is occasionally locked against displacement. By locking the magnetic head against displacement, with the recording medium not being loaded in position, it is possible to prevent destruction of the magnetic head.
Up to now, such a recording medium having a recording capacity on formatting equal to approximately 1.44 Mbytes, for example, a flexible disc, referred to hereinafter as a lower-order recording medium, is used extensively. Recently, such a recording medium having the increased recording capacity at the time of formatting equal to 150 to 650 Mbytes, referred to hereinafter as an upper-order recording medium, as al result of reducing the track width, has been proposed. In this upper-order recording medium, the position information of the data track is stored in the data track. Meanwhile, the position information of the data track is not stored in the lower-order recording medium.
In consideration of co-existence of the lower-order recording medium and the upper-order recording medium, such a recording/reproducing apparatus is proposed which records/reproduces the information signals for both recording mediums. For example, in a certain recording/reproducing apparatus, a linear motor operating as a voice coil motor is used to shift the magnetic head along the radius of the recording medium.
In this type of the recording/reproducing apparatus, in which the driving means for the magnetic head is constituted by a voice coil motor, the magnetic head is locked against displacement, in the state in which the recording medium is loaded thereon, as described above, in order to prevent possible destruction of the magnetic head.
However, if, with the magnetic head locked against displacement, the track feed requesting pulse arrives from the external computer, the magnetic head is not moved, as a result of which the magnetic head position envisaged by the external computer differs from the actual magnetic head position. That is, in a recording/reproducing apparatus constructed so that it cannot instantly respond to the track feed requesting pulse due to, for example, the above-mentioned locking, the magnetic head occasionally cannot be fed to the desired track position.
It is therefore an object of the present invention to provide a recording/reproducing method and apparatus whereby the track feed can be positively performed responsive to the oncoming track feed requesting pulse.